Construction Projects: To Rebaseline or Not to Rebaseline, That Is the Question...
March 30, 2022
Construction Projects: To Rebaseline or Not to Rebaseline, That Is the Question...Download Article
Irrespective of any specified contractual requirements regarding the provision of a schedule, one of the first goals of the management team on a large construction project should be the production of a baseline schedule which can be used to communicate the construction execution strategy, to manage and monitor the progress of the works and, probably most importantly, provide a tool to allow reliable forecasting for the ongoing works.
Tracking what actually happened against what was planned is always useful for historical purposes. However, it is the effectiveness of the forecasting features of a well-constructed baseline that will allow the schedule to become a tool that can facilitate effective pre-emptive management decision making.
Over the course of a project, changes might be instructed. Execution strategies, methods and sequences are sometimes altered due to unforeseen prevailing conditions, for example, COVID-19. Actual performance may not be as expected, and other external events may take place, such as inclement weather. All the above may influence actual progress as measured against the original baseline schedule.
Assuming the contract is silent on the matter2, the question is: At what point is it appropriate to consider a rebaseline to the project schedule?
Throughout my planning career, I have worked with several organisations that have implemented various methods in an attempt to empirically quantify when the rebaselining of a schedule could, or should, occur.
Some methods used a percentage change in scope as a measure (for example, a specified increase in quantities or cost). Others looked at specified variances against earned value ratings and some tested a point at which the original completion date could not be met even when reasonable mitigation strategies were modelled (such as the use of ‘what-if’ scenarios). One organisation had a principle in place to measure when the incline of the installation S-curves3 had reached a specified increased gradient rate as a point that would trigger discussions about whether a rebaseline was required.
All these methods had some merit in that they at least provided guidance for the empirical measurement of project transformation that a construction team could use as a benchmark for assessing their decision to rebaseline, or not, as the case may be.
In my experience of ‘live’ project planning, when a schedule can no longer be used to effectively direct or forecast the design, procurement, construction or commissioning activities then the project team will lose faith in the plan. They may then ignore it completely or even start to do their ‘own thing’ in order to get the job done. In these cases, the schedule merely becomes a recording tool and is of no benefit for managing the ongoing work. The works then start to be executed in an uncoordinated manner and confidence and morale suffers on the project.
The contemporaneous execution strategies might become so far removed from those envisaged at the outset of the project that the exercise of measuring progress back to a far distant baseline becomes virtually impossible or irrelevant.
Deciding whether to formally rebaseline sometimes turns upon political considerations. There may be a reluctance to rebaseline (especially to a later completion date) as this action can be perceived as declaring failure or culpability.
Creating the illusion that an original completion date is still feasible may provide the opportunity to hopefully claim that any future (non-culpable) events that occur were the driver for late completion. The schedule then becomes a political tool rather than a management tool.
Minimising the confusion of constant planning flux
Rebaselining should be undertaken sparingly and in controlled circumstances (or, of course, as may be required by the contract conditions) to reduce the potential confusion of constant planning flux.
There can be situations when taking the rebaseline ‘hit’ to the original schedule at the appropriate point may be the best thing to do. “Suffering the slings and arrows4” which that decision may cause in the short term (i.e. “bear the ills we have5”), may turn out to be better than “to fly to others that we know not of6” and the prospect of years in dispute, the outcome of which may be uncertain.
In respect to Hamlet’s conundrum stated above (spoiler alert…), unfortunately, that story didn’t end well for him, but the rebaseline question can end well for you if you adequately record the matters at hand and have a considered rebaselining procedure process in place.
Stephen Podesta is a planner and delay analyst who advises both domestic and international clients and contractors on construction time-related matters and enjoys the plays of Shakespeare.
1: William Shakespeare’s play Hamlet, Act 3, Scene 1: the “To be, or not to be” soliloquy.
2: For example, the NEC Contract requires that the original (first) ‘Accepted Programme’ (effectively the ‘Baseline’) is to be revised and resubmitted (at intervals as stated within the Contract) for a new ‘Acceptance’ process by the Project Manager. In this case the programme is effectively ‘Rebaselined’ at each stated interval.
3: S-Curves represent cumulative work planned and completed (plotted on the y-axis, expressed in quantity or percentage) over time (plotted on the x-axis, generally expressed in either hours, days, weeks or months).
4: William Shakespeare’s play Hamlet, Act 3, Scene 1: the “To be, or not to be” soliloquy.
5: William Shakespeare’s play Hamlet, Act 3, Scene 1: the “To be, or not to be” soliloquy.
6: William Shakespeare’s play Hamlet, Act 3, Scene 1: the “To be, or not to be” soliloquy.